In a known pedal system, a foot operated pedal, operable with an operator's toe pressed thereagainst, is pivotally mounted on a foot support that is installed on the floor surface of a vehicle operator cab, for supporting a heel part of the operator (See Patent Document 1). There has been known another technique according to which a foot operated pedal is constituted by a lower pedal and an upper pedal that is mounted over the lower pedal so as to be adjustably movable between a plurality of positions in relation to the lower pedal and the angle of the operator's foot relative to the foot operated pedal is varied by adjusting the position of the upper pedal relative to the lower pedal (See e.g., Patent Document 2).
Patent Document 1: JP-A-2007-109162
Patent Document 2: JP-UM-A-6-78053
The pedal system disclosed in Patent Document 1 suffers from the problem that it does not use a means for adjusting the angle of the foot relative to the foot operated pedal and therefore has poor pedal operability depending on the physical size of the operator and causes great fatigue to the operator.
Although the technique of Patent Document 2 may conceivably be applied to the pedal system of Patent Document 1, this case involves a double structure composed of the lower pedal and the upper pedal placed thereon and, in addition, entails structural complications because the upper pedal has to be adjustably movable between a plurality of positions in relation to the lower pedal.